Adenovirus infection may be more common than suspected

Rachel Tompa

Human adenoviruses come in more than 50 known types, and are common and usually harmless in healthy adults. Recently, these viruses have drawn attention in the HIV vaccine field, due to associations found between adenovirus 5 infection and increased risk of HIV acquisition in vaccine recipients in the HVTN’s Step study. Those findings led VIDD staff physician Dr. Marcel Curlin and colleagues to look at the prevalence of adenovirus infection in HIV-positive men who have sex with men, to better understand how common adenovirus exposure may be in this high risk group.

There has been little interest in defining human adenovirus infections in adults in detail, especially using novel sampling techniques and new molecular assays. To better inform future trials using adenovirus-based vaccines, Curlin and colleagues looked at the shedding rates of all adenovirus types in 20 HIV positive Peruvian men who have sex with men.

The researchers used genital and anal swabs that were collected in an earlier study three times a week for 18 weeks, and looked for presence of adenovirus using a sensitive PCR technique. In contrast to past studies using less sensitive means of detection, which found adenovirus shedding in only a quarter of HIV positive individuals, Curlin’s group found that 75 percent of the study group shed adenovirus at some point during the study. More than 20 different adenovirus types were identified, and some men were infected with multiple types. The findings suggest adenovirus infections are commonly acquired subclinically. The researchers also identified several new adenovirus subtypes in the process. These findings may be important to consider in trials of new adenovirus-based vaccines for HIV and other diseases, as they show that exposure to adenoviruses may occur frequently in certain populations.